Quantum Information Processing
Quantum Information Processing
We have a number of programmes related to ultimate Si devices and quantum information processing in particular using electron spins as qubits for quantum computation. The SEM image on the right shows a 50 nm wide oxidised n-Si wire with a number of side gates to electrostatically deplete the wire into quantum dots.
The quantum dots formed by applying voltages to four of the side gates in the figure above demonstrate Coulomb blockade oscillations as a fifth gate is swept to change the number of electrons on the quantum dot.
The quantum dots formed by the electrostatic side gates are still relatively large with around 100 or so electrons in each dot. Therefore we are developing smaller quantum dots using rap-around aluminium gates as shown on the right. The oxidised silicon wire is now only 20 nm wide with three 20 nm long gates and two side gates to control the electron number on the quantum dots.
